In 2014-15, he received 706 presents – more than any of his Royal relations – including a cuddly toy wombat, a possum skin cloak, an amphibious boat, a personalised surfboard, a rocking horse, two pairs of sheepskin boots and a bike.

The Duke and Duchess joined thousands of spectators to cheer on Sir Ben's Land Rover BAR team compete on the Solent in the America's Cup World Series (ACWS).

The Duchess enters into the spirit of the dayCredit:
James Whatling

The royal couple began the day by visiting the home crew's base in Portsmouth, Hampshire, where they were shown the team's state-of-the-art testing boats.

They were met by a group of youngsters who had been out with the team ahead of the racing through The 1851 Trust, the Land Rover BAR affiliated charity of which Kate is the royal patron. The charity is aimed at getting children involved in the maritime industry.

The Duke and Duchess cheer on the America's Cup World SeriesCredit:
Lloyd Images

They also met 10-year-old Zak Kay, from St Paul's Catholic Primary School in Portsmouth, who won a competition to design the trophy for the Portsmouth ACWS event and asked the Duke about Prince George’s birthday.

The royal couple were then given a tour of the boat shed in the headquarters where they saw the team's test boats before boarding a small boat to go out to watch the six teams taking part in the second and final day of the racing.

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Sir Ben was not present for the tour as he was on the water preparing for the day's racing.

The US team won the final race, but a second-place finish for Sir Ben's team was enough to secure them victory in the weekend regatta overall.

The day saw the Duchess of Cambridge also spent time with young people working in the sailing and marine industry, speaking to them about working to reduce the stigma of mental health problems.

Prince George enjoys a pre-birthday treat at the Royal International Air Tattoo at RAF FairfordCredit:
PA wire

Tiyah Windslade, 17, who presented the Duchess with a bouquet, said: "She was lovely beautiful and friendly.

"I almost started crying! She said that I would be in safe hands with Ben Ainslie.

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"She spoke a lot about mental health and how we need to stop people from feeling ashamed about themselves and come out and be very open about their mental health. And she sad that we are the voice reaching out to people because we are working with them on the ground.

"The Duke was talking about the same priorities as the Duchess. He was really lovely too."